Relief valve



`Nov. 20, 1951 .1.' MERCIER RELIEF VALVE Filed Feb. 12, 194e l l l l l 1 4.

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JEAN M ERC: E@

INVENTOR,

l BY mmh LEA A'TI'ORNEY Patented Nov. 20, 1951 Jean Mercier, New York, N. Y.

Application February 12., 1946, Serial No. 646,968 y i In France November 14, 1941 Section 1, Public Law 690, August 8, 1946 Patent expires November 14, 1961 l The present invention relates to devices for discharging air or other gases present in conduits or containers containing liquids, and par- 4 Claims. (Cl. 137-53) ticularly liquids under pressure, such as, for inp stance, in hydraulic brake conduits, in conduits l of alternative pumps under hydraulic control, in conduits of central steam and hot water heating and the like.

It is known that the operation of an installation which is hydraulically controlled is sub- "J'ect to irregularities due to the presence in its conduits of `air or gas, and that it is necessary toaccomplish an evacuation of such air and 'gas in order to insure proper functioning of the u ,q

installations.

` All the devices used heretofore for this pur- 'pose are subject to certain disadvantages due tothe very principle of their operation, and it is the object of the present invention to eliminate these disadvantages.

V The device according to the present invention is based on a novel principle. Its operation depends on a diiferencein pressure which occurs between two zones in communication with each other.` One of these zones is also in permanent communication with the medium from which the air or gas is to be discharged.` The second Azone communicates with the atmosphere by means of a valve, each increase in the pressure prevailing in the medium to be evacuated creating the desired pressure difference which in its turn determines the opening of the valve.

According to one embodiment of the invention the two zones are separated by a wall provided with at least one orifice. 4According to another embodiment, the `two vzones are formed. in a singleunitary space.

The invention will be better understood with the aid of the accompanying drawing which exemplilies illustratively two embodiments of the invention.

In the drawing:

Fig. 1 is a sectional View of a device according to one embodiment of the present invention; and Fig.l 2 is a similar sectional View of a device :according to a Asecond embodiment.

Referring rst to Fig. 1, I is the body of an air or gas discharge device according to the inyention inserted in a conduit containing a liquid. ,The 'device as shown in Fig. 1 comprises two :chambers 2 and 3.` The chamber 2 communicates permanently and directly with the liquid carrying conduit and the chamber 3 can be brought into communication with atmosphere by means of a gas escape port controlled by a, valve 4.

The two chambers are separated by a Wall 5 provided with two orces 6 and l. Two diaphragms 8 and 9 are provided in the bottom of the device and in its upper portion, respectively, said diaphragms being connected by a rod l0 which. in the embodiment shown, passes through a central opening in the Wall 5. i l

According to Fig. l, the orifice 6 is formed by the play provided between the rodA l0 and the central opening in the Wall 5. The wall 5 has a conical form and the orifice l is made at the lower edge of the cone while the orifice 6 is disposed in the apex of the cone. In this manner the air or the gas which accumulates in the upper portion of chamber 2 passes easilyint the chamber 3 through the passage 6, whlethe orifice l facilitates the circulation. The upper portion of the chamber 3 can be brought into communication with the atmosphere through a gas escape port Il provided in the carrier l2 of the diaphragm 9. The port l l is normally closed by the valve 4. When an increase in pressure occurs in the liquid carrying conduit, this increase will not be immediately transmitted to the chamber 3, and, consequently, the diaphragm 8 is subject to an excess pressure which causes a displacement of the rod l0 downwardly, thus opening the valve 4 and permitting the air or gas which has accumulated in the chamber`3 after passing the orifice 6 to escape into the atmosphere. As soon as the excess pressure ceases, the rod I0 returns to its normal position `and the valve 4 is closed. Thus the device operates at each increase of pressure in the liquid carrying conduit and the discharge of the air or gas is effected automatically. In the case of ja hydraulic brake system, the device operates at reach operation of the brake so that discharge of air or gas is insured in a simple manner.

In the embodiment of the invention illustrated in Fig. 1 the two zones 2 and 3 are separated by a xed or stationary Wall 5. It should be understood that the device could function even in the absence of the wall 5. In efect, the air perfect and very or gas would accumulate automatically inthe i upper portion of the chamber 2-3 and the two zones necessary for the operation of the device would be created automatically even without a separation wall. However, this wall insures a better functioning of the device, and, conse` quently, it is present in the preferred'embodiments of the invention. The Wall 5 could have any desired shape, but it is preferable to give it a conveniently inclined shape such as, for ex adapted to be connected to a liquidvlled system at the highest point thereof, and provided at its top with a gas escape port leading to the atmosphere, valve means including a movable memcontrolled by the movable wall i3. The uppln portion of the device is formed by a cover I4 pro-r`r vided with a gas escape port l5. The port/1 5 is closed by the valve Iii carried on a rod Il rigid with the movable wall I3. in its normal position by a spring I8 which insures closing of the valve. The loweisurfalce of the wall I3 is inclined and one orifice I9 is formed in the highest portion of the wall I-Swhile another ber and normally closing saidgas escape port, said chamber being subdivided'into a lower and 'an upperoompartment communicating Vwith each `other through at least one restricted passage. and

amovable element rigidwith said movable'memper of said valve means and having two opposite surfaces exposed to the pressures in said upper The wall {'3v is held and lower compartments, respectively, said surfaces Ihaving active areas so dimensioned that the jvalve 'means remains closed, regardless of pres orifice is provided in the lowest portion of IsaidV Wall. In this manner air or gas which accumuf lates in the chamber 2 can pass into the chamber 3. VAs soon as an increase of pressure occurs injthe pressure liquidecontaining conduit the movable wall I3 is upwardly displaced so as to lift the valve i6, whereupon the air or gas accu# mulated in the Vchamber 3 is discharged to 'the atmosphere.

MThe operation `of the device according to Fig. A2 is based on the same' principle as that of 'the -device according Vto Fig. 1 with the difference, however, that inthe arrangement according to FigQZ the wall is indispensable because the openiingof'the valve .i6 on 'each increase of pressure is 'causedby the :displacement of this wall.

tshould be understood that the device according tothe invention canbe used with any conduit or container whatever which contains liquid in jorder 'to insure an automatic discharge of air or gas on each 'increase of pressure in the conduit or container. It is particularly intended to use these -devices in connection with thel conduits of hydraulic brakes.'

It 'should also be understood that the invention i s notlimited to 'the examples shown, and that the 'air or gas discharge devices according to the invention can be constructed in various different y forms without'deviating from the spirit fof the invention. Particularly, in the case Vof adevice of 'the type shown in Fig. 1 in which the separatfingwalli's not absolutely necessary, lthe movable element vcan'b'e Vformed in any suitable manner vother than by diaphragms. Moreover, the 'conn'e'ction between these movable elements 'can be efeoted 'by external meansreplacing the rod I0. Finally, if a Vwall is provided, such wallo may 'assume Vany desired convenient form and the oricefor orices'may be disposed at any pointer points desired.

Thjejsame applies to the device according to Fig. '2. YThe movable wall can also assume Vany v convenient form as may the valve, etc.V

Finally, it should be understood that the in- 1. A device for discharging gaseous impurities fromdiquid filled systems, comprising a chamber having at its bottom level an entry port sure variations inthe liquid filled system aslong as both compartments are filled with liquid but opens in 'response to rapid pressure fiuctuations V`in the liquid system and in the lower compartment whenever a cushion of gas has accumulated in the upper compartment. 2. A de vice as claimed `in claim l, in which said movable element is a piston slidable insaid chamber and which serves to sub-divide the'same yintoupper and lower compartments, the surface of said piston facing said 'lower compartment being inclined from the horizontal, `one restricted passage throughsaid piston opening into said lower compartment being provide'd'at-the.highest .pointof `said inclined surface, and a second restricted passage through :said ipiston opening into `said lower compartment rbeing `.provided -at-the lowest point o f vsaid inclined surface. Y.

3. A device as claimed kin claim 1, in whichrsaid escape .port is formed as astationary valve seat. and said movable member is a valve-cooperating with said seat, said movablemember including la ,piston vertically s ldable in saidchamber subfdiv-iding saidrchamber into an upper and a lower fcompartment, `a rod projecting fromvth'e upper 4. A deviceas claimed in claim 1, in whichsaid chamberjsgsubdivided by a stationary transverse `wall and `said movable element includes two vdiaphragms :,closingsaid chamber at its upper and lower .'ends, respectively, .and a -rod connecting :said diaphragme, :said gas .escape port being Y'formed inithe upper ';iiaphragmand axed abutment closes said `gas Vescape Aport when said dia- `phragmsassumeitheirinormal positions. Y

MERCIER.

@if REFnRENCEs errno The Vfollowing ireferencesfare -of record-in lth'e iile of this patent:

UNITED STATES PATENTS liixriber,V .Name f ir Y 'Date v j 351,994 Moore NOV.' 2,1886 2,197,148 Hasbrouck Apr.,16, 1940 Number Country Date 35,974 4Switzerland Jan. 20, 41906 "230,121 switzerland 1T 1944 

